Table 1 Baseline demographic and clinical characteristics

 Male, n (%)

7 (64%)

 Age (years)

59 ± 14

 BMI (kg/m²)

29 ± 8

Clinical illness severity

 Time from disease onset to ICU admission, days

9 (6–10)

 Time from ventilation initiation to enrollment, days

17.3 ± 8.6

 Time from disease onset to enrollment, days

26.0 ± 8.2

 Chronic APACHE

  A

  B

  C

  D

6 (55%)

5 (45%)

0

0

Comorbidities

 Coronary artery disease, n (%)

1 (9%)

 Hypertension, n (%)

4 (36%)

 Diabetes, n (%)

2 (18%)

 Neoplasia, n (%)

3 (27%)

Ventilatory variables at enrollment

 Tidal volume (mL)

364.5 ± 72.0

 Tidal volume per predicted body weight (mL/kg of PBW)

5.38 ± 0.58

 Respiratory rate (breaths per minute)

24 ± 2

 Total PEEP (cmH₂O)

12.6 ± 2.9

 Peak inspiratory pressure (cmH₂O)

32.2 ± 2.2

 Plateau pressure (cmH₂O)

26.8 ± 2.4

 Driving pressure (cmH₂O)

14.2 ± 1.2

 Respiratory system compliance (mL/cmH₂O)

25.9 ± 5.9

 Lung compliance (mL/cmH₂O)

28.7 ± 6.1

 Chest-wall compliance (mL/cmH₂O)

152 (120.2–305.1)

 Mean airway pressure (cmH₂O)

17.0 ± 2.8

 Minute ventilation (L)

8.8 ± 2.3

 Ventilatory ratio

2.1 ± 0.4

 Inspiratory esophageal pressure (cmH₂O)

14.9 ± 3.4

 Expiratory esophageal pressure (cmH₂O)

12.8 ± 3.1

Gas exchange at enrollment

 P_aO₂ (mmHg)

88.2 (77.1–127.6)

 P_aCO₂ (mmHg)

55.9 ± 6.6

 pH

7.371 ± 0.03

 P_aO₂/F_iO₂ (mmHg)

163 (109–220)

 F_iO₂ (%)

60 (50–65)

 End-tidal CO₂ (mmHg)

42 (39–50)

 Dead space (%)

18.6 (12.6–27.1)

 Shunt fraction (%)

15.5 (7.1–27.3)